1. Field of the Invention
This invention relates to compounds which are useful additives for lubricating oils. In particular, this invention is directed toward lubricating oil compositions containing neutral or overbased derivatives of ortho-carboxy phenylphenone. The neutral derivatives of ortho-carboxy phenylphenones provide detergency for the lubricating oil; whereas, the overbased derivatives of ortho-carboxy phenylphenones additionally provide an alkaline reserve for the lubricating oil.
2. Background of the Invention
U.S. Pat. No. 3,526,661 discloses that alkaryl keto acids amidated by reaction with aliphatic polyamines are useful sludge dispersancy and detergency additives for lubricating oils.
U.S. Pat. No. 4,379,092 discloses a process for the preparation of ortho-carboxy phenyllphenones. These compounds are taught as intermediates in the synthesis of anthraquinones, which themselves are taught as being used for dyestuffs, paper pulp industries and for the manufacture of hydrogen peroxide.
Great Britain Application No. 1,450,733 discloses aroyl benzoic acids as useful starting materials for dyes and insecticides.
Other alkyl-substituted ortho-carboxy phenylphenones are disclosed in CA 80:47709(e); CA 83:146931(q); CA 84:179413(w); CA 94:15446(q); and U.S. Pat. Nos. 3,880,892 and 3,816,124. Salts of lower alkyl-substituted ortho-carboxy phenylphenones are disclosed in CA 82:172012(q). However, there is no teaching in these references, or apparently elsewhere, to prepare overbased derivatives of ortho-carboxy phenylphenones or to add either the neutral or overbased derivatives of ortho-carboxy phenylphenones to lubricating oil.